Department of Chemistry, Northern Kentucky University, Highland Heights, Kentucky 41099, USA.
Environ Sci Technol. 2010 Jun 1;44(11):4116-21. doi: 10.1021/es902040u.
The interaction of catechol with chromium(III) oxide (Cr(2)O(3)), manganese dioxide (MnO(2)), iron(III) oxide (Fe(2)O(3)), and titanium dioxide (TiO(2)) was evaluated as a function of pH conditions (pH 3-10) and ionic strength using a combined approach of bulk adsorption, attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), and dissolution analysis. Adsorption of catechol showed a strong pH-dependent behavior with the metal oxides, remaining constant under acidic-neutral pH (3-7) and increasing under more basic conditions. In situ ATR-FTIR measurements indicate that catechol binds predominately as an outer-sphere complex on MnO(2) and as an inner-sphere complex on Fe(2)O(3), TiO(2), and Cr(2)O(3) substrates. Catechol complexation on Fe(2)O(3), TiO(2), and Cr(2)O(3) promotes dissolution at pH >5, whereas MnO(2) dissolution occurs under acidic and basic conditions (pH 3-10).
儿茶酚与三氧化铬（Cr(2)O(3)）、二氧化锰（MnO(2)）、三氧化二铁（Fe(2)O(3)）和二氧化钛（TiO(2)）的相互作用作为 pH 条件（pH 3-10）和离子强度的函数进行了评估，使用批量吸附、衰减全反射傅里叶变换红外光谱（ATR-FTIR）和溶解分析的组合方法。儿茶酚在金属氧化物上的吸附表现出强烈的 pH 依赖性，在酸性-中性 pH（3-7）下保持不变，在更碱性条件下增加。原位 ATR-FTIR 测量表明，儿茶酚主要在 MnO(2)上作为外球络合物，在 Fe(2)O(3)、TiO(2)和 Cr(2)O(3)基质上作为内球络合物结合。儿茶酚与 Fe(2)O(3)、TiO(2)和 Cr(2)O(3)的络合在 pH >5 时促进溶解，而 MnO(2)在酸性和碱性条件下（pH 3-10）发生溶解。
